CBSE Class 9 Science Chapter 03 Tissues In Action MCQs Set 02

Answer: (A) At the base of the internode or just above the node

Explanation:
The intercalary meristem sits at the base of an internode or just above a node, so even after the top of a stem is removed, this tissue keeps dividing and pushes out new branches from the nodes.

Answer: (A) Meristematic cells losing the ability to divide and taking on a specialised structure and function

Explanation:
Not every new cell produced by a meristem stays meristematic; some cells stop dividing and change shape and structure to specialise for jobs like support or transport. This specialisation process is what the chapter calls differentiation, turning meristematic tissue into permanent tissue.

Answer: (A) They increase the surface area for absorbing water and minerals from soil

Explanation:
Root hair are projections of the epidermis that expand the contact area between the root and surrounding soil, letting the plant take up more water and minerals efficiently.

Answer: (A) It helps the plant float in water

Explanation:
Ordinary parenchyma stores food and carries out photosynthesis, but in aquatic plants a specialised version develops air-filled spaces that act like tiny floats, keeping the plant buoyant in water.

Answer: (A) Sclerenchyma cells are mostly dead with lignin-thickened walls, while collenchyma cells are living with pectin-thickened corners

Explanation:
• Sclerenchyma has thick, lignified walls, is largely made of dead cells, and gives hardness (found in nutshells, husks, stems)
• Collenchyma has living cells with pectin deposited unevenly at the corners, giving flexibility rather than rigidity
• So the two tissues serve opposite ends of the support spectrum — rigid strength versus bendable support

Answer: (A) It has several layers of cells with tightly packed flat outer cells that resist wear and microbial entry

Explanation:
Tissue exposed to constant friction and injury, like skin or the oesophagus lining, is built from many stacked layers with a tough, flattened outer surface, unlike the single thin layer used where quick exchange of gases is the priority.

Answer: (A) Ligament

Explanation:
Ligaments join bone to bone and limit excessive movement at a joint, which is exactly the role described here; tendons, by contrast, link muscle to bone to produce movement rather than restrict it.

Answer: (A) It has a soft, jelly-like matrix that gives flexibility and cushioning

Explanation:
Bone gets its hardness from a mineral-rich matrix, but cartilage's matrix is soft and gel-like, which is why it can be compressed and still return to its original shape instead of cracking.

Answer: (A) Dendrites

Explanation:
Dendrites branch out from the neuron to receive incoming signals; the axon then carries the message onward, ending at axon terminals that pass it to the next cell.

Answer: (A) Unbranched, multinucleate, cylindrical cells showing striations

Explanation:
This description matches skeletal muscle, which is attached to bones and under conscious control. Smooth muscle instead has spindle-shaped, unstriated cells, and cardiac muscle has branched fibres with faint striations — both work involuntarily.

Answer: (A) Ball and socket joint

Explanation:
The rounded head of the upper arm bone sits inside a shallow socket of the shoulder bone, and this arrangement, called a ball and socket joint, permits movement in many directions rather than just one plane.

Answer: (A) Flexible cartilage joining the ribs to the sternum allows the cage to expand and contract

Explanation:
Although ribs form a strong protective cage around the heart and lungs, their attachment to the breastbone through flexible cartilage lets the whole cage widen and narrow, changing chest volume and drawing air in and out.

Answer: (A) They cushion the vertebrae and allow bending and twisting without damaging the spinal cord

Explanation:
Because the vertebral column has to both support the body and stay flexible, cartilage discs sit between the small bones of the spine acting as shock absorbers, protecting the delicate spinal cord while still permitting movement.

Answer: (A) Leukemia and thalassemia

Explanation:
Bone marrow stem cells can divide and give rise to new blood cells, so transplanting healthy stem cells into a patient is used as a treatment for blood cancers such as leukemia and blood disorders such as thalassemia.

Answer: (A) A blend of science, satire and culture describing a botanical excursion through the Western Ghats

Explanation:
Swamy's book, written in Kannada, mixes scientific observation with satire and cultural storytelling, drawing on his travels through forests of the Western Ghats to document plants, their uses, folklore and conservation, work that earned it a Kendra Sahitya Akademi Award.

Answer: (B) Cell - tissue - organ - organ system

Explanation:
Similar cells group into a tissue, tissues combine to build an organ, organs join to form an organ system, and organ systems together make up the whole organism.

Answer: (B) Animal cells lack a rigid cell wall

Explanation:
Plant cells are boxed in by a rigid cell wall that keeps their shape fixed, but animal cells have no such wall, so they can deform easily.
This flexibility is part of why animal bodies are suited to movement while plants remain fixed in place.

Answer: (C) The thickness or diameter of the stem

Explanation:
Girth is used in the chapter to mean how thick or wide a stem becomes, which is different from growth in length caused by apical meristems.

Answer: (A) Animals have tissues to digest food from outside sources, while plants have tissues that make food using sunlight

Explanation:
Animal tissues break down food obtained from external sources, whereas plant tissues capture solar energy through photosynthesis to build their own food components.
This fundamental difference in nutrition is one reason plant and animal tissues are structured so differently.

Answer: (B) Rapid exchange of gases and liquids

Explanation:
A thin, single-celled layer offers the shortest possible path for substances to cross, making it ideal for quick diffusion, which is exactly the arrangement seen lining blood vessels and lungs.

Answer: (C) White blood cells

Explanation:
• WBCs gather at the site of infection to fight invading microbes
• Their accumulation causes the visible redness and swelling
• Pus forms from dead WBCs and microbes at the infected spot

Answer: (B) Due to haemoglobin in red blood cells, which live for about four months

Explanation:
Haemoglobin, an iron-rich protein packed inside red blood cells, gives blood its colour. These cells are not permanent though — they survive roughly four months before the body replaces them.

Answer: (B) About 12-15 per cent

Explanation:
The chapter notes that bones typically make up 12 to 15 per cent of an adult's body weight, though this figure shifts somewhat depending on age, sex and overall body composition.

Answer: (C) The collarbone

Explanation:
Along with the shoulder bone forming the ball-and-socket joint, the collarbone joins in to complete the shoulder girdle, which links the arm firmly to the skeleton.

Answer: (B) Totipotency

Explanation:
This capacity of a mature cell to give rise to a complete organism, much like a zygote does, is called totipotency, and cells with this ability are termed totipotent.